upsilon
[ yoop-suh-lon, -luh n, uhp-; especially British yoop-sahy-luh n ]
/ ˈyup səˌlɒn, -lən, ˈʌp-; especially British yupˈsaɪ lən /
noun
the 20th letter of the Greek alphabet (Υ, υ).
the vowel sound represented by this letter.
Also called upsilon particle. Physics.
any of a family of heavy, short-lived, neutral mesons that are composed of a bottom quark and its antiquark. Symbol: Υ, υ
Origin of upsilon
1615–25; < Late Greek
ŷ psīlón literally, simple
u (to distinguish it from the digraph
oi, pronounced the same in LGk)
Words nearby upsilon
upside,
upside down,
upside the head,
upside-down cake,
upsides,
upsilon,
upsilon particle,
upsize,
upskill,
upspin,
upspring
British Dictionary definitions for upsilon particle
upsilon
/ (ˈʌpsɪˌlɒn, juːpˈsaɪlən) /
noun
the 20th letter in the Greek alphabet (Υ, υ), a vowel, transliterated as y or u
Word Origin for upsilon
C17: from Medieval Greek
u psilon simple
u, name adopted for graphic
u to avoid confusion with graphic
oi, since pronunciation was the same for both in Late Greek
Medical definitions for upsilon particle
upsilon
n.
The 20th letter of the Greek alphabet.
Scientific definitions for upsilon particle
upsilon particle
[ ŭp′sə-lŏn′, yōōp′- ]
An electrically neutral meson having a mass 18,513 times that of the electron and a mean lifetime of approximately 8.0 X 10-20 seconds. See Table at subatomic particle.